SN54HC161, SN74HC161

4BIT SYNCHRONOUS BINARY COUNTERS

SCLS297D − JANUARY 1996 − REVISED SEPTEMBER 2003

9

POST OFFICE BOX 655303

PARAMETER MEASUREMENT INFORMATION

VOLTAGE WAVEFORMS

SETUP AND HOLD AND INPUT RISE AND FALL TIMES

VOLTAGE WAVEFORMS

PULSE DURATIONS

th

tsu

50%

50%

50%

10%

10%

90%

90%

VCC

VCC

0 V

0 V

tr

tf

Reference

Input

Data

Input

50%

High-Level

Pulse

50%

VCC

0 V

50%

50%

VCC

0 V

tw

Low-Level

Pulse

VOLTAGE WAVEFORMS

PROPAGATION DELAY AND OUTPUT TRANSITION TIMES

50%

50%

50%

10%

10%

90%

90%

VCC

VOH

VOL

0 V

tr

tf

Input

In-Phase

Output

50%

tPLH

tPHL

50%

50%

10%

10%

90%

90%

VOH

VOL

tr

tf

tPHL

tPLH

Out-of-Phase

Output

NOTES: A. CL includes probe and test-fixture capacitance.

B. Phase relationships between waveforms were chosen arbitrarily. All input pulses are supplied by generators having the following

characteristics: PRR

≤ 1 MHz, ZO = 50 Ω, tr = 6 ns, tf = 6 ns.

C. For clock inputs, fmax is measured when the input duty cycle is 50%.

D. The outputs are measured one at a time with one input transition per measurement.

E. tPLH and tPHL are the same as tpd.

Test

Point

From Output

Under Test

CL = 50 pF

(see Note A)

LOAD CIRCUIT

Figure 1. Load Circuit and Voltage Waveforms